Hi Terry,
Please refer to the F2806x documentation and header files for how ONESHOT operates and where the bit is in the ADC registers.
This was a documentation/header file oversight that these have not been updated for the F2802x and F2803x. You can copy the changes in the F2806x header files to the F2803x/F2802x header files and everything should work.
Note that ONESHOT mode is only useful if the workaround used for the first sample issue is to set ADCCLK = 30MHz and to enable Non-overlap. Otherwise, ONESHOT causes conversions one at a time, which are all bad due to the first sample erratum.